The demographics of a television viewing audience are typically used by television program producers to improve the marketability of their television programming and determine a best price for advertising during such programming. In addition, accurate television viewing demographics allow advertisers to target commercial content to desired segments of the population.
In order to determine these demographics, an audience measurement company may enlist a plurality of television viewers as panelists. The viewing habits of the enlisted viewers and demographic data about the enlisted viewers are collected and used to determine statistically the demographics of a television viewing audience.
One aspect of audience measurement involves determining the identity of the content being displayed on a television. Conventional audience measurement systems use channel detection techniques to identify the channel to which a television set is tuned (i.e., channel information). This channel information may then be combined with programming information (e.g., a program schedule) to identify the program that was being displayed on the television during the time at which the television was tuned to the detected channel.
In addition, audience members may use a television to consume media from one or more alternate sources, such as a digital versatile/video disk (DVD) player, a video cassette recorder (VCR), game console, personal computer, etc. For example, audience members may use a television for gaming, gambling, shopping, and video on demand, to name a few. While the alternate sources of media may not originate from a broadcaster (e.g., sources such as a DVD player, VCR, video game console, etc.), measurement of the alternate sources may enhance measurement of demographic profiles and viewing habits of the enlisted viewers.
In addition to detecting a channel to which a television is tuned, channel detection systems are used to detect channel change events in which a television stops displaying programming associated with a first channel and begins displaying programming associated with a second channel. Because a channel change event corresponds to a change in the programming being displayed to the programming audience, a channel change event may be used as a trigger to start one or more methods to obtain identification data about the new programming being displayed to the audience.
Additionally, a channel change event and/or a switch to one or more alternate media sources (hereinafter “media change event”) often corresponds with a change in the audience membership and, therefore, may also be used to trigger a method for capturing information about the audience. For example, audience measurement systems may include a device, such as a people meter, having a set of input keys, each assigned to represent a single viewer. The people meter may be adapted to capture information about the audience by prompting the audience members to indicate that they are present in the viewing audience by, for example, pressing the appropriate input key disposed on the people meter. Using a media change event as a trigger for people meter prompting allows for the accurate recording of changes in the size and/or membership of the audience that may result from the media change event or that may have caused the media change event.